Depth gauge

ABSTRACT

A depth gauge for measuring the depth of blind holes in bones and/or nails inserted into bones. The measurement tool comprises: a probe with an abutment at its end to engage against the distal edge of the blind hole; a tubular body; and a grooved insert. After the probe, lying into the tubular body, is positioned through the blind hole to be measured, the grooved insert is slid forward inside the tubular body, surrounding the probe, and pushing the probe sideward, towards the blind hole wall. When probe and groove insert are retracted together, they firmly engage against the distal bone wall. The tubular housing is then pushed forward until it abuts against the proximal bone wall, allowing even in small diameter holes, an accurate reading of hole depth on the scale located at the rear end of the probe.

BACKGROUND OF THE INVENTION

This invention generally relates to measurement devices and more particularly to depth gauges for determining the depth of holes.

It is often necessary to exactly assess the depth of a blind hole. Existing measurement devices have a single hook on one end of a calibrated rod. The rod is inserted through the hole, and after the hook emerged through the opposite, distal wall, the rod is retracted until it abuts against the blind edge of the hole. The disadvantage of these devices is that hooking the edge of the hole through the far wall could be quite difficult, mainly when measuring smaller diameter holes.

For the foregoing deficiencies in the prior art, a new hole depth-measuring instrument that provides a fast and accurate measure is needed. There is a further need to have an instrument wherein the probe firmly engages to the distal edge of the hole, allowing a precise measurement of the depth of a blind hole.

BRIEF SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide a simple and effective tool to measure the depth of a blind hole.

Another object of the invention herein is to provide an instrument wherein the probe firmly engages to the distal edge of the hole, allowing a precise measurement of the depth of a blind hole.

The preferred embodiment of the present invention comprises a probe which has opposed proximal and distal ends, wherein a scale located at the proximal end of the probe defines an axis and presents indicia along the axis, and the probe has an abutment at its distal end; a tubular housing which is slidably mounted on the scale located on the probe; and a grooved insert which has opposed proximal and distal ends. The distal end of the grooved insert tapers to a sharp edge.

By fulfilling the recently mentioned objects, the present invention is extremely helpful to the medical care area.

Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Preferred features of the present invention are disclosed in the accompanying drawings, wherein similar reference characters denote similar elements throughout the several views, and wherein:

FIG. 1 is a perspective view of the depth gauge system.

FIG. 2 is a perspective view of the disassembled depth gauge system.

FIG. 3 is a side view of the step 1 of the surgical technique.

FIG. 4 is a side view of the step 2 of the surgical technique.

FIG. 5 is a side view of the step 3 of the surgical technique.

FIG. 6 is a side view of the step 4 of the surgical technique.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, the preferred embodiment of the present invention will be described with reference to FIGS. 1-2.

FIG. 1 shows the preferred embodiment of the depth-measuring tool of the present invention. The probe 1, engaged into the groove 5 of the grooved insert 4, is able to slide freely respect to the grooved insert 4 along the longitudinal axis of the probe 1. The tubular housing 8 slidably mounted over probe 1 and grooved insert 4.

The disassembled system is clearly seen in FIG. 2, wherein its three components are shown: the probe 1; the grooved insert 4; and the tubular housing 8. The probe has an abutment 2 on its distal end and a scale 3 located at its proximal end. The grooved insert 4 includes a groove 5 to accommodate the probe 1, a proximal end 7, and a tapered distal end 6 designed to avoid impingement against the proximal border of the hole to be measured 10. The tubular housing 8 is sized to accommodate the grooved insert 4 and the probe 1 inside it.

Hereinafter, a method of depth measuring according to the preferred embodiment of the present invention will be explained with reference to FIGS. 3-6.

When the grooved insert 4 is retracted, the probe 1 is easily inserted into and through the bone hole 9, while the tubular housing 8 lying at the back, as best shown in FIG. 3.

The grooved insert 4 is then slid forward until its final destination pushing the probe 1 up, towards the upper bone hole wall 10, as clearly shown in FIG. 4. The tapered distal end 6 of the grooved insert 4 avoids the grooved insert 4 to abut against the bone hole wall 10.

When the probe 1 and the grooved insert 4 are retracted together respect to the bone 9, the abutment 2 at the probe 1 firmly engages against the distal bone wall as shown in FIG. 5.

FIG. 6 shows the final step of the measurement procedure. The tubular housing 8 is pushed forward until it abuts against the proximal bone wall, allowing an accurate reading of hole depth on the scale 3 located at the rear end of the probe 1.

While I have illustrated and described a preferred embodiment of the invention, it will be understood that those skilled in the art will thereby be enabled to devise variations and modifications without departing from the spirit and scope of this invention, as defined in the appended claims. 

1. A measurement instrument for measuring blind holes in bones, the instrument comprising: a) an elongated probe having opposed proximal and distal ends; b) a scale located adjacent the proximal end of the probe, defining an axis and presenting indicia extending along the axis; c) an abutment on the distal end of the probe, able to slide through the hole to be measured; d) a grooved insert with a transverse section that matches the probe transverse section; e) the grooved insert being able to slide back and forward respect to the probe along the longitudinal axis of the probe; f the grooved insert having a distal end that tapers to a sharp edge; e) wherein the forward movement of the grooved insert over the probe up to its final destination does not enable probe and groove to be retracted out of the hole together; e) a housing slidably mounted on the scale; and wherein relative movement between the tubular housing and the scale causes the abutment on the distal end of the probe to protrude from the tubular housing a selected distance reflected by the indicia.
 2. A measurement instrument for targeting an intramedullary nail after nail insertion into the bone, the instrument comprising: a) an elongated probe having opposed proximal and distal ends; b) a scale located adjacent the proximal end of the probe, defining an axis and including indicia extending along the axis; c) a male thread on the proximal end of the probe; d) a female threaded device that matches with the male thread on the probe; e) an abutment on the distal end of the probe; f) a grooved insert with a transverse section that matches with the probe transverse section; g) the grooved insert being able to slide back and forward respect to the probe along the longitudinal axis of the probe; h) the grooved insert having a distal end that tapers to a sharp edge; i) wherein the forward movement of the grooved insert over the probe up to its final destination does not enable probe and groove to be pulled back out of the hole together; j) a housing slidably mounted on the scale; k) wherein the forward movement of the grooved insert over the probe, and the subsequent probe and groove jointly retraction causes the abutment at the probe end to engage firmly against the far border of the nail hole; and l) the female threaded device pushing the tubular housing against the proximal bone wall, while allowing the scale to mark the exact position of the nail being targeted. 